Olympio Cipriano's Blog

Story based burndown chart options

olympio — Thu, 29 Mar 2012 16:52:32 +0300

I've been using scrum for a quite long time now and my team usually makes use of story based sprints. This is not the most common but in my opinion is better than task based sprints since we (and the client) care more about stories than tasks.

The problem with this approach is that the most common burn down charts doesn't give the information we need to know when running a sprint. The basic burn down chart is something like this:

In this picture we can see the ideal story point’s burn down. The main issue here is that this graph doesn't take the team speed into account and it might be more appropriate for task based burn downs. Also, this graph doesn't considerer the intrinsic discrete characteristic of a story based burn down where we should only decrease the value of the graph if the story is closed. Futhermore the graph should remain a flat line indicating that we didn’t accomplish our goal. Also, the ‘ideal’ line shows a continuous decreasing burn down, which of course cannot be achieved (but this is why it is called ‘ideal’ anyway :D).

The main point here is that we can make this burn down chart look better and make the 'ideal' more real if we consider the team speed and the discrete characteristic of this kind of burn down. The following graph shows a burn down chart that takes theses information into account.

This example considers a team with 10 days sprint and speed of 27 points. The presented sprint has the following story points ordered by priority.

Respecting the story priorities in this table and considering the average team speed we can construct the graph above. For example, to beat a 13 points story we will need at least 4 days of work. Also, looking to the interval between days 2 and 4 in the graph we can say that the team will not be delayed if they remain with the same story points burned.

The new information included in this graph is the team speed, the discrete characteristic of the burn down and the story priority.

Using this graph with all these new information the team can certainly evaluate much better their performance during the sprint.

Symbian Anna and Native Widget with Non-UI based application

olympio — Wed, 03 Aug 2011 17:14:56 +0300

Hello,

I've been struggling with Symbian Anna native widget for a while now. The problem was that even with a fully functional widget example compiled with the N97 SDK and installed in Symbian Anna I couldn't get my application running properly on that device. The problem with my application was that after a reboot, my previously added home screen widget would just disappear. The same behavior didn't happen with the provided SDK example. The only difference I noticed between the example and my application was that the first was a GUI application and the second wasn't.

Looking into the code you can notice one big difference between these two kinds of applications which is the fact that the GUI application registers itself in the phone menu application. This is achieved by using the *_reg.rss file. This file specifies application's name and icon. My guess at that point was that information was being used by the Home Screen Manager to find the associated widget application after a reboot and keeps its widget in the Home Screen.

I then tried to register my console application in the phone menu application. As my application was supposed to be just a widget, I set the attribute 'hidden' in the *_reg.rss file.

The good news is that solves the problem. Now my application widget is not removed after a reboot.

Hope that my experience helps someone...

Symbian Anna and Native Home Screen Widget

olympio — Tue, 19 Jul 2011 00:50:02 +0300

Hello,

Symbian Anna has been released few days ago. Unfortunately it still lacks an API to develop native Home Screen widgets. In fact, such API doesn't make part of Symbian^3 either. The native Home Screen API (HsWidgetPublisher) was introduced in the N97 SDK with the N97 being the first Nokia device to come with Home Screen.

When Symbian^3 SDK was released it contained a warning in its release notes telling the HsWidgetPublisher was deprecated. In fact, although the headers of such API were still present in the SDK, the binaries needed to compile against were not packed with SDKs. As the same situation held for the Symbian Anna SDK I tried to compile a Home Screen widget with the old N97 SDK and test it against the pretty new Symbian Anna device available to me, the X7. The result was that, despite the warning indicating the application was not compatible with the phone, the N97 SDK Home Screen Widget example run very well in the X7. I’ve also tested the same binary with N8 and E7 and got the same result.

The conclusion: the same API binaries are still being shipped with the devices. So if you want to develop high performance widgets you can still use the deprecated HsWidgetPublisher API. Just download the N97 SDK, develop your widget and install it wherever you want. :)

That's it.

Symbian^3 and SymbianOSUnit Compilation Issues

olympio — Tue, 08 Feb 2011 23:21:33 +0200

Although there is a lot of buzz around the future of Symbian and what OS Nokia should adopt in its place, there are a lot of developing still running over it. If Nokia plans to change its focus and leave Symbian for a Android or even Windows Phone 7 this will occur gradually. Also, if Nokia keeps Symbian as its choice for OS there will be still a lot of development with Symbian/C++ since Qt still needs to get more APIs available (QtMobility project) to encompass all the developer needs.

So the point is that the development with Symbian OS, as like any other platform, needs to support unit tests. The Symbian always had a pretty good open project for that: SymbianOSUnit . The latest available version dates from 2008-05-13. Besides that it works pretty well in S60 5th edition. The problem happens when it comes to Symbian^3 SDK. Unfortunately there are a lot of missing files when trying to compile it for the first time. To fix this the developer needs to add some missing system paths in the file SymbianOSUnit\SymbianOSUnitApp\group\S60_3RD\SymbianOSUnit.source

SYSTEMINCLUDE \epoc32\include\mw

SYSTEMINCLUDE \epoc32\include\platform

SYSTEMINCLUDE \epoc32\include\platform\mw

Other problem that was preventing a successful compilation was a missing macro in the Logger.cpp file of the SymbianOSUnitApp project. The macro __PROFILE_RESET at line 31 that used to be defined in file e32def.h is now defined in file e32def_private.h under the platform folder. The solution is to add the following include in the Logger.cpp file.

#include <e32def_private.h>

After these changes the SymbianOSUnit can compile and run again.

Nokia to launch application supporting interactivity for the brazillian digital television standard

olympio — Fri, 07 May 2010 01:30:36 +0300

It seems that Nokia Brasil is going to launch Ginga middleware (brazillian specification for interactivity) in the middle of 2010 (source in portuguese).

The brazillian digital television standard is similar to DVB european standard (it is partially based on it). Nokia has already launched its digital television player application in the end of 2009 (it is available in ovi store for N85, n97, etc). This solution uses the nokia mobile tv receiver SU-33Wb, a variation of the already available SU-33W used with the european standard.

This 6 months gap shows that things are running fast in this area in brazil due to market pressure and competition among manufactures (LG and Samsung are running to launch their versions of the Ginga middleware).

As the brazillian digital television is new and more advanced in terms of interactivity than the previous ones like DVB, there is a big market to explore.

So, stay tunned to opportunities.

Filling a gap of Mobile Extensions

olympio — Mon, 11 May 2009 20:04:15 +0300

The mobile extensions released some time ago had the lack of Bluetooth support. Bluetooth communication is very important in many applications especially in games. To fill in this gap students of the Federal University of Campina Grande (Brazil) have developed some C++ wrappers to Symbian OS Bluetooth APIs so that Qt and Open C++ developers can use then with no knowledge of Symbian/C++ programming.

More information can be found in http://efforts.embedded.ufcg.edu.br/symbiancpp/?p=30

Notice that this is the first release of the API.

We hope to get feedback from everybody to improve whatever is needed.